2023 Monster SP crank case breather valve leaking…

[GunghoDucati]

Arriving home home following a ride, I notice a small amount of oil that leaked out from the top of the crank case breather valve. The location was close to the rear shock mount. I cleaned the exterior and checked the hose clamp from the valve as secure. Any guidance on possible cause for this small reoccurring oil leak? I am trying to trouble shoot source and cause. There is very little on this issue available. I ordered a new stock bleeder valve from my dealer but hope someone can provide details if familiar with this valve and the oil leak issue. Are there other tests or checks I should consider?

 

[HighwaySoul]

Make sure the breather valve doesn't have any cracks or isn't bent out of shape. Also, check the breather hose to be sure it's not pinched or blocked, otherwise, pressure might build up

 

[MasterMonster]

Arriving home home following a ride, I notice a small amount of oil that leaked out from the top of the crank case breather valve. The location was close to the rear shock mount. I cleaned the exterior and checked the hose clamp from the valve as secure. Any guidance on possible cause for this small reoccurring oil leak? I am trying to trouble shoot source and cause. There is very little on this issue available. I ordered a new stock bleeder valve from my dealer but hope someone can provide details if familiar with this valve and the oil leak issue. Are there other tests or checks I should consider?

That's a bummer on a new bike!! Usually it's just a bit of weepage from the breather hose connection or a bad seal on the valve itself, but the new valve you ordered should fix it. Before you swap it out though, I also suggest what @HighwaySoul said.. double-check that the hose going to the valve isn't kinked or blocked anywhere, and that the clamp is properly seated. Sometimes a little bit of excess crankcase pressure from a tiny obstruction can cause that kind of weeping. It's usually not a big deal, just a bit of a mess. Let us know if the new valve fixes it!

 

[duca.ster]

Since you've got a new one on order, that's the right first step, but while you wait, make sure the breather hose isn't kinked or clogged and that the airbox end is clear. If the new valve doesn't solve it, then I'd start looking at blow by from rings or overfilling oil, but nine times out of ten the valve swap sorts it